RE: [PATCH 22/32] ACPICA: actbl2: Replace 1-element arrays with flexible arrays

From: Kees Cook
Date: Wed Apr 05 2023 - 20:45:09 EST




On April 5, 2023 5:22:55 PM PDT, Dan Williams <dan.j.williams@xxxxxxxxx> wrote:
>Dan Williams wrote:
>> Rafael J. Wysocki wrote:
>> > From: Kees Cook <kees@xxxxxxxxxxx>
>> >
>> > ACPICA commit 44f1af0664599e87bebc3a1260692baa27b2f264
>> >
>> > Similar to "Replace one-element array with flexible-array", replace the
>> > 1-element array with a proper flexible array member as defined by C99.
>> >
>> > This allows the code to operate without tripping compile-time and run-
>> > time bounds checkers (e.g. via __builtin_object_size(), -fsanitize=bounds,
>> > and/or -fstrict-flex-arrays=3).
>> >
>> > The sizeof() uses with struct acpi_nfit_flush_address and struct
>> > acpi_nfit_smbios have been adjusted to drop the open-coded subtraction
>> > of the trailing single element. The result is no binary differences in
>> > .text nor .data sections.
>> >
>> > Link: https://github.com/acpica/acpica/commit/44f1af06
>> > Signed-off-by: Bob Moore <robert.moore@xxxxxxxxx>
>> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>>
>> Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx>
>
>Unit tests say NAK, though.
>
>This causes a regression, but I think I see where. Will send a fixed
>patch in a bit.

Ah, which tests? I must have missed something!

Thanks for digging in.

-Kees


--
Kees Cook